Alcohol consumption during pregnancy by women from southern Brazil: a cross-sectional study

ABSTRACT BACKGROUND: Some maternal characteristics are related to alcohol intake during pregnancy, which irreversibly compromises the maternal-fetal binomial integrity. OBJECTIVES: To identify the frequency, impact, and factors associated with alcohol consumption during pregnancy. DESIGN AND SETTING: A cross-sectional study was performed at the Hospital Materno Infantil Presidente Vargas (HMIPV) in Porto Alegre/RS between March and December 2016. METHODS: A structured questionnaire was administered along with a medical records review. They refer to the maternal sociodemographic and gestational status, alcohol consumption patterns, and characteristics of the fetus/newborn. In the statistical analysis, P values < 0.05 were considered significant. RESULTS: The frequency of alcohol intake was 37.3%; this was characterized by the consumption of fermented beverages (89.3%), especially during the first trimester (79.6%). Risky consumption (high and/or early) occurred for 30.2% of participants. Risk factors associated with maternal alcohol consumption during pregnancy were tobacco use (P < 0.001) and abortion attempt (P = 0.023). Living with a partner (P = 0.002) and planning pregnancy (P = 0.009) were protective factors. Risky consumption was related to all of the aforementioned variables as well as threatened abortion (P = 0.023). CONCLUSIONS: Alcohol intake during pregnancy is common and affects nearly one-third of pregnant women. Knowledge of the population at risk and protective factors is essential for the development of campaigns that seek to reduce consumption and, therefore, its consequences for the mother and fetus.


INTRODUCTION
Health problems related to alcohol consumption are usually associated with males.However, changes in the social role of women have led to a decrease in this difference. 1Over time, a progressive rise in the use and abuse of alcohol by women has been observed, 2 even at childbearing age, which has led to an increasing number of obstetric and neonatal complications. 3 According to the World Health Organization (WHO), the global prevalence of alcohol intake is 9.8%. 4[7] Some maternal characteristics are associated with an increased frequency and amount of alcohol intake during pregnancy.These include lifestyle, psychological factors, alcohol consumption patterns, concomitant drug use, social vulnerability, and aspects related to family structure, such as single motherhood. 8The lack of prenatal care and pregnancy planning also appears to be important predisposing factors. 9,10cohol can cause injuries in one in every 100 live births exposed during pregnancy, 11 and there is no safe consumption amount.Therefore, abstinence is the best and safest conduct to be OBJECTIVE Considering the scarcity of Brazilian epidemiological studies related to this issue, our aim was to identify the impact and factors associated with alcohol intake in pregnant women who gave birth at a reference hospital in southern Brazil.

METHODS
This was a prospective cross-sectional study carried out at the Hospital Materno Infantil Presidente Vargas (HMIPV) that included pregnant and postpartum women and their respective newborns who utilized the hospital's obstetrics service at birth from March to December 2016.All patients were users of the Unified Health System (in Portuguese, Sistema Único de Saúde -SUS), which is the current public health system in Brazil.The HMIPV is located at Porto Alegre and is a reference hospital for maternal and child care in the State of Rio Grande do Sul (RS).
Trained members conducted a pilot study and applied the clinical protocol.Data were collected through direct interviews with puerperal women during rooming in shortly after delivery.
The medical records of the mothers and their respective newborns were also reviewed.The data collected included sociodemographic and gestational history findings, fetuse/newborns characteristics, and the use of drugs, including alcohol, during pregnancy.The sample comprised 570 women who were divided into two groups: 1) those who did and 2) did not consume alcohol during pregnancy.
Maternal age was stratified into women aged 20 years or younger, those 21-34 years, and those 35 years or older. 16Origin was classified by whether the patient lived in Porto Alegre, metropolitan region, or countryside town of the state.Puerperal women's education was classified as incomplete elementary education, complete elementary education, and complete secondary education to higher education. 17The number of residents per house into two groups: from one to five and from six to 14 individuals. 18Family income was categorized into one minimum wage (BRL 880.00 at the moment of the study) or more per household.Women were divided into primiparous or multiparous groups according to their number of pregnancies. 19Prenatal care was divided by trimester of beginning (in first, second, or third) 20 and by consultations number (fewer than six or six or more). 21men were asked about quarter(s) of alcohol consumption; alcohol amount consumed and intensity, frequency, and type of drink.All beverage measurements were converted and presented according to international (10 g of pure alcohol per serving) 22 and national standards (14 g of pure alcohol per serving).This corresponds to approximately 350 mL of beer, 150 mL of wine, or 45 mL of hard liquor. 2 Alcohol consumption amount was categorized as low (1-20 g/ day), moderate (21-40 g/day) or high (≥ 41 g/day). 23Binge drinking episodes and heavy episodic drinking were assessed according to WHO guidelines and defined as the consumption of 60 g or more of pure alcohol, or about four servings or more on at least one occasion. 22Drink types were questioned and classified into fermented (beer, sparkling wine, and wine) and distillates (whiskey, vodka, "cachaça, " "caipirinha, " and tequila).Consumption frequency was classified as monthly or less, two to four times a month, two to three times a week, or four or more times a week.
Women who answered affirmatively to at least one of the following variables were categorized as engaging in risky consumption: period of use in the first trimester, consumption frequency of four or more times a week, high amount consumption (≥ 41 g/day), or positive for binge drinking episodes. 24ematurity was defined as gestational age at birth less than 37 weeks 25 and low birth weight as below 2,500 grams. 26For Apgar scores, values greater or less than 7 were considered at the first and fifth minutes of life. 27When fetal malformations were present, they were classified as isolated or multiple and specified according to the medical records description.In assessing microcephaly, the measurement of the newborns head circumference was considered both for gestational age at birth (absolute) and after correction, considering baby's length (relative or true). 28e results for qualitative variables are presented as frequencies and percentages, and the quantitative variables are shown as averages and standard deviations.Normality was verified using the Shapiro-Wilk test and histogram inspection.Sociodemographic and gestational factors associated with alcohol consumption were evaluated using a Poisson regression analysis with robust variance adjustment.Prevalence ratio (PR) measurements are presented with a 95% confidence interval.For multivariate analysis, variables with P < 0.20 in the Wald test were selected.To evaluate the characteristics of fetuses and live births, Student's t-test and chisquare tests were applied, as was Fisher's exact test when appropriate.The results were considered statistically significant at P < 0.05.The study was only performed after informed consent assignment.

RESULTS
The total sample consisted of 570 women, ages ranging from 12 to 45 years (mean 25.1, SD ± 7.1).Gestation was recognized at an average of 11.6 weeks.Paternal ages ranged from 15 to 60 years (mean 28.5, SD ± 8.5).The average number of maternal pregnancies was 2.32 (range 1-12).
Age was similar between women who consume and did not consume alcohol (mean age of 24.9 [SD ± 6.8] and 25.2 years [SD ± 7.2] respectively; P = 0.5887).Most women who drank alcohol during pregnancy consumed low amounts (64.2%; moderate: 16.9%; high: 18.9%).However, approximately one in every four women (24.9%) reported binge drinking episodes.Fermented beverages were the main type of beverage consumed (89.3%), with beer representing the most common (82.1%), followed by vodka (17%) and wine (9.2%).Almost 13% of women drank both fermented and distilled beverages during pregnancy.Most drank monthly or less (63.9%; two to four times a month: 27.4%; two to three times a week: 6.7%; and four or more times a week: 1.9%).The first trimester was the most commonly reported period of alcohol use (79.6%), with a decreasing trend in the other trimesters (second trimester: 48.3%; third trimester: 33.6%).Continuous use throughout pregnancy was reported by 21.8% of women.
Drinking during pregnancy was associated with both concomitant use of illicit (PR = 2.20; 95%CI: 1.72-2.80;P < 0.001) and licit drugs (tobacco; PR = 1.96; 95%CI: 1.61-2.39;P < 0.001) as well as use during the first trimester of pregnancy (P < 0.001).Alcohol intake during gestation occurred in 78.3% of women who had used illicit drugs and 59.6% of those who smoked.Approximately three out of four marijuana users had consumed alcohol.Only eight women reported using cocaine (3.8%), and three crack (1.4%).All of them reported using alcohol simultaneously (Table 3).
None fetal or newborn characteristic was associated with consumption of alcoholic beverages by women.However, 'multiple" malformations were most predominant in the group of fetuses exposed to alcohol (46.2%;Table 4).

DISCUSSION
This study identified a high frequency of alcohol consumption in pregnant women (37.3%), similar to other Brazilian studies, such as those that took place in São Paulo (33.3%), 6 Rio de Janeiro (40.6%), 28 and Teresina (32.4%). 29These frequencies are higher than those reported in developed countries (10.2%). 30In addition to methodological and sampling differences, some factors, such as effectiveness of public health policies and cultural disparities, may have contributed to such inequalities. 26In general, alcohol consumption in developed countries is seen more negatively than in Latin America. 31 The results obtained in our study about the use of alcohol in the first trimester of pregnancy and the occurrence of binge drinking episodes among pregnant women were cause for concern.They were similar to those reported by other authors 9,10 and highlight the progressive tendency of the female population to consume more alcohol at abusive levels. 32Early consumption of alcohol within the first trimester has been associated with a 12-fold greater chance of fetal involvement.Moreover, excessive levels of alcohol intake have increased the risk for worse neonatal outcomes. 33cohol consumption most often occurred in an occasional way and in low quantities; this fact reflects the underestimation   Valid variables with P < 0.20 in the Wald test were included in the analysis; Risk consumption considered women who answered affirmatively to at least one of the variables: quantity (high > = 41g/day), frequency (4 or > week), EBP (positive), and consumption in the first trimester; PR = Adjusted prevalence ratio; CI = Confidence interval.
of the harmful effects even for small amounts. 11In addition, the drinks mainly consisted of fermented beverages, especially beer and derivatives, which may also demonstrate an underestimation of the potential risk of these beverages compared to distilled drinks. 34e absence of a partner has been shown to be closely related to alcohol consumption by women during pregnancy. 8,9,13According to the Centers for Disease Control and Prevention (CDC), alcohol consumption is almost twice as common among pregnant women with no partner.In addition, the frequency of excessive consumption among these women is significantly higher. 35This finding is often related to other risk factors for alcohol consumption, such as unplanned pregnancies, as well as low socioeconomic status, with the mothers usually being the main or only providers of income. 36tably, in the present study, the presence of a partner was a protective factor for alcohol consumption, which may be related to greater financial and emotional stability as well as family support.
Another protective factor identified in this study was pregnancy planning.There are reports in literature of substantially less alcohol consumption by women during pregnancy when there is intention and planning to become pregnant. 9,37Failure to plan and, consequently, delay to recognize the pregnancy, can lead many women to engage in harmful behaviors, including the consumption of alcoholic beverages. 10This fact helps to clarify the high frequency of alcohol intake (79.6%) during the first trimester observed in our study.In addition, women tend to be more careful about what they consume when pregnancy is planned, as they are more aware of possible risks for the fetus due to alcohol consumption. 38e use of pregnancy termination methods was associated with risky alcohol intake in our sample..39 This may be linked to pregnancy rejection because it is unwanted.
Threatened abortion was the only variable that showed an exclusive association with at-risk alcohol consumption in this study.
According to the literature, 40 women who consume more than five drinks per week have a significantly greater chance of miscarriage.
This problem occurs because alcohol is one of the main substances responsible for childbirth-related problems. 41 previously described in the literature, 5,15,41 we found that smoking was an important factor associated with risky alcohol consumption.The simultaneous use of alcohol and tobacco can be explained by the legality and wide availability of these substances as well as by the common maternal risk factors for their use during pregnancy, which are usually related to the vulnerability presented by these women. 42In addition, studies have identified neurotransmitters and nicotine receptors that interact with both substances and mediate effects involved not only in their sensitivity but also in dependence. 43e most discussed and described fetal malformations associated with alcohol consumption belong to the spectrum of findings observed in individuals with FAS. 14 However, some studies point to possible associations between maternal alcohol consumption and the occurrence of other anomalies. 43In the present study, no major fetal/neonatal malformation was associated with the consumption of this substance.Alcohol can cross the placental barrier and directly interfere with embryonic and fetal development.However, there is no single mechanism that can explain all of the harmful effects of alcohol on the fetus or the precise alcohol amount that can cause malformations. 9her factors have been associated with alcohol consumption during pregnancy, such as low education and socioeconomic level, advanced maternal age, and lack of prenatal care.Address for correspondence: conceptualization (equal), data curation (equal), formal analysis (equal), funding acquisition (equal), methodology (equal), project administration (equal), resources (equal), software (equal), supervision (equal), validation (equal), visualization (equal), writing-original draft (equal), and writing-review and editing (equal); Telles JAB: conceptualization (equal), data curation (equal), formal analysis (equal), funding acquisition (equal), methodology (equal), project administration (equal), resources (equal), software (equal), supervision (equal), validation (equal), visualization (equal), writing-original draft (equal), and writing-review and editing (equal); Cunha AC: conceptualization (equal), data curation (equal), formal analysis (equal), funding acquisition (equal), methodology (equal), project administration (equal), resources (equal), software (equal), supervision (equal), validation (equal), visualization (equal), writingoriginal draft (equal), and writing-review and editing (equal); Zen PRG conceptualization (equal), data curation (equal), formal analysis (equal), funding acquisition (equal), methodology (equal), project administration (equal), resources (equal), software (equal), supervision (equal), validation (equal), visualization (equal), writing-original draft (equal), and writingreview and editing (equal); and Rosa RFM: conceptualization (equal), data curation (equal), formal analysis (equal), funding acquisition (equal), methodology (equal), project administration (equal), resources (equal), software (equal), supervision (equal), validation (equal), visualization (equal), writing-original draft (equal), and writing-review and editing (equal).All authors contributed substantially to the conception and design, data collection, analysis, and interpretation of data; writing of the article; critical review of the intellectual content, and final approval of the submitted version.Sources of funding: None Conflicts of interest: None Date of first submission: May 27, 2023 Last received: January 09, 2024 Accepted: February 08, 2024

Table 1 .
Consumption of alcoholic beverages according to maternal sociodemographic characteristics Quantitative variables are presented as means and standard deviations in the text; *Number of valid answers; PR = Crude prevalence ratio; CI = Confidence interval.

Table 2 .
Consumption of alcoholic beverages according to gestational characteristics *Number of valid answers; PR = Crude prevalence ratio; CI = Confidence interval.

Table 3 .
Consumption of alcoholic beverages according to concomitant use of drugs during pregnancy *Number of valid answers; PR = Crude prevalence ratio; CI = Confidence interval.

Table 4 .
Fetus or newborn characteristics according to maternal consumption of alcoholic beverages during pregnancy *Relative microcephaly corrected for the length of the baby; Apgar 1<7/Apgar 5<7 = values greater or less than 7 in the first and fifth minutes of life; a. Number of fetuses/neonates, considering deaths and valid responses; PR = Crude prevalence ratio; CI = Confidence interval.

Table 5 .
Multiple regression analysis of factors associated with alcohol consumption during pregnancy

Table 6 .
Multiple regression analysis of factors associated with risky consumption during pregnancy